Merge branch 'timers/core' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into remove-local-timers

19 files changed, 1031 insertions, 394 deletions

diff --git a/kernel/cpu/idle.c b/kernel/cpu/idle.c
index 8b86c0c68edf..d5585f5e038e 100644
--- a/kernel/cpu/idle.c
+++ b/kernel/cpu/idle.c
@@ -40,11 +40,13 @@ __setup("hlt", cpu_idle_nopoll_setup);
 
 static inline int cpu_idle_poll(void)
 {
+	rcu_idle_enter();
 	trace_cpu_idle_rcuidle(0, smp_processor_id());
 	local_irq_enable();
 	while (!need_resched())
 		cpu_relax();
 	trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
+	rcu_idle_exit();
 	return 1;
 }
 
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 6b41c1899a8b..9dc297faf7c0 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4394,6 +4394,64 @@ perf_event_read_event(struct perf_event *event,
 	perf_output_end(&handle);
 }
 
+typedef int  (perf_event_aux_match_cb)(struct perf_event *event, void *data);
+typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data);
+
+static void
+perf_event_aux_ctx(struct perf_event_context *ctx,
+		   perf_event_aux_match_cb match,
+		   perf_event_aux_output_cb output,
+		   void *data)
+{
+	struct perf_event *event;
+
+	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
+		if (event->state < PERF_EVENT_STATE_INACTIVE)
+			continue;
+		if (!event_filter_match(event))
+			continue;
+		if (match(event, data))
+			output(event, data);
+	}
+}
+
+static void
+perf_event_aux(perf_event_aux_match_cb match,
+	       perf_event_aux_output_cb output,
+	       void *data,
+	       struct perf_event_context *task_ctx)
+{
+	struct perf_cpu_context *cpuctx;
+	struct perf_event_context *ctx;
+	struct pmu *pmu;
+	int ctxn;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(pmu, &pmus, entry) {
+		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
+		if (cpuctx->unique_pmu != pmu)
+			goto next;
+		perf_event_aux_ctx(&cpuctx->ctx, match, output, data);
+		if (task_ctx)
+			goto next;
+		ctxn = pmu->task_ctx_nr;
+		if (ctxn < 0)
+			goto next;
+		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
+		if (ctx)
+			perf_event_aux_ctx(ctx, match, output, data);
+next:
+		put_cpu_ptr(pmu->pmu_cpu_context);
+	}
+
+	if (task_ctx) {
+		preempt_disable();
+		perf_event_aux_ctx(task_ctx, match, output, data);
+		preempt_enable();
+	}
+	rcu_read_unlock();
+}
+
 /*
  * task tracking -- fork/exit
  *
@@ -4416,8 +4474,9 @@ struct perf_task_event {
 };
 
 static void perf_event_task_output(struct perf_event *event,
-				     struct perf_task_event *task_event)
+				   void *data)
 {
+	struct perf_task_event *task_event = data;
 	struct perf_output_handle handle;
 	struct perf_sample_data	sample;
 	struct task_struct *task = task_event->task;
@@ -4445,62 +4504,11 @@ out:
 	task_event->event_id.header.size = size;
 }
 
-static int perf_event_task_match(struct perf_event *event)
-{
-	if (event->state < PERF_EVENT_STATE_INACTIVE)
-		return 0;
-
-	if (!event_filter_match(event))
-		return 0;
-
-	if (event->attr.comm || event->attr.mmap ||
-	    event->attr.mmap_data || event->attr.task)
-		return 1;
-
-	return 0;
-}
-
-static void perf_event_task_ctx(struct perf_event_context *ctx,
-				  struct perf_task_event *task_event)
+static int perf_event_task_match(struct perf_event *event,
+				 void *data __maybe_unused)
 {
-	struct perf_event *event;
-
-	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
-		if (perf_event_task_match(event))
-			perf_event_task_output(event, task_event);
-	}
-}
-
-static void perf_event_task_event(struct perf_task_event *task_event)
-{
-	struct perf_cpu_context *cpuctx;
-	struct perf_event_context *ctx;
-	struct pmu *pmu;
-	int ctxn;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(pmu, &pmus, entry) {
-		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->unique_pmu != pmu)
-			goto next;
-		perf_event_task_ctx(&cpuctx->ctx, task_event);
-
-		ctx = task_event->task_ctx;
-		if (!ctx) {
-			ctxn = pmu->task_ctx_nr;
-			if (ctxn < 0)
-				goto next;
-			ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
-			if (ctx)
-				perf_event_task_ctx(ctx, task_event);
-		}
-next:
-		put_cpu_ptr(pmu->pmu_cpu_context);
-	}
-	if (task_event->task_ctx)
-		perf_event_task_ctx(task_event->task_ctx, task_event);
-
-	rcu_read_unlock();
+	return event->attr.comm || event->attr.mmap ||
+	       event->attr.mmap_data || event->attr.task;
 }
 
 static void perf_event_task(struct task_struct *task,
@@ -4531,7 +4539,10 @@ static void perf_event_task(struct task_struct *task,
 		},
 	};
 
-	perf_event_task_event(&task_event);
+	perf_event_aux(perf_event_task_match,
+		       perf_event_task_output,
+		       &task_event,
+		       task_ctx);
 }
 
 void perf_event_fork(struct task_struct *task)
@@ -4557,8 +4568,9 @@ struct perf_comm_event {
 };
 
 static void perf_event_comm_output(struct perf_event *event,
-				     struct perf_comm_event *comm_event)
+				   void *data)
 {
+	struct perf_comm_event *comm_event = data;
 	struct perf_output_handle handle;
 	struct perf_sample_data sample;
 	int size = comm_event->event_id.header.size;
@@ -4585,39 +4597,16 @@ out:
 	comm_event->event_id.header.size = size;
 }
 
-static int perf_event_comm_match(struct perf_event *event)
-{
-	if (event->state < PERF_EVENT_STATE_INACTIVE)
-		return 0;
-
-	if (!event_filter_match(event))
-		return 0;
-
-	if (event->attr.comm)
-		return 1;
-
-	return 0;
-}
-
-static void perf_event_comm_ctx(struct perf_event_context *ctx,
-				  struct perf_comm_event *comm_event)
+static int perf_event_comm_match(struct perf_event *event,
+				 void *data __maybe_unused)
 {
-	struct perf_event *event;
-
-	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
-		if (perf_event_comm_match(event))
-			perf_event_comm_output(event, comm_event);
-	}
+	return event->attr.comm;
 }
 
 static void perf_event_comm_event(struct perf_comm_event *comm_event)
 {
-	struct perf_cpu_context *cpuctx;
-	struct perf_event_context *ctx;
 	char comm[TASK_COMM_LEN];
 	unsigned int size;
-	struct pmu *pmu;
-	int ctxn;
 
 	memset(comm, 0, sizeof(comm));
 	strlcpy(comm, comm_event->task->comm, sizeof(comm));
@@ -4627,24 +4616,11 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
 	comm_event->comm_size = size;
 
 	comm_event->event_id.header.size = sizeof(comm_event->event_id) + size;
-	rcu_read_lock();
-	list_for_each_entry_rcu(pmu, &pmus, entry) {
-		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->unique_pmu != pmu)
-			goto next;
-		perf_event_comm_ctx(&cpuctx->ctx, comm_event);
 
-		ctxn = pmu->task_ctx_nr;
-		if (ctxn < 0)
-			goto next;
-
-		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
-		if (ctx)
-			perf_event_comm_ctx(ctx, comm_event);
-next:
-		put_cpu_ptr(pmu->pmu_cpu_context);
-	}
-	rcu_read_unlock();
+	perf_event_aux(perf_event_comm_match,
+		       perf_event_comm_output,
+		       comm_event,
+		       NULL);
 }
 
 void perf_event_comm(struct task_struct *task)
@@ -4706,8 +4682,9 @@ struct perf_mmap_event {
 };
 
 static void perf_event_mmap_output(struct perf_event *event,
-				     struct perf_mmap_event *mmap_event)
+				   void *data)
 {
+	struct perf_mmap_event *mmap_event = data;
 	struct perf_output_handle handle;
 	struct perf_sample_data sample;
 	int size = mmap_event->event_id.header.size;
@@ -4734,46 +4711,24 @@ out:
 }
 
 static int perf_event_mmap_match(struct perf_event *event,
-				   struct perf_mmap_event *mmap_event,
-				   int executable)
-{
-	if (event->state < PERF_EVENT_STATE_INACTIVE)
-		return 0;
-
-	if (!event_filter_match(event))
-		return 0;
-
-	if ((!executable && event->attr.mmap_data) ||
-	    (executable && event->attr.mmap))
-		return 1;
-
-	return 0;
-}
-
-static void perf_event_mmap_ctx(struct perf_event_context *ctx,
-				  struct perf_mmap_event *mmap_event,
-				  int executable)
+				 void *data)
 {
-	struct perf_event *event;
+	struct perf_mmap_event *mmap_event = data;
+	struct vm_area_struct *vma = mmap_event->vma;
+	int executable = vma->vm_flags & VM_EXEC;
 
-	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
-		if (perf_event_mmap_match(event, mmap_event, executable))
-			perf_event_mmap_output(event, mmap_event);
-	}
+	return (!executable && event->attr.mmap_data) ||
+	       (executable && event->attr.mmap);
 }
 
 static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
 {
-	struct perf_cpu_context *cpuctx;
-	struct perf_event_context *ctx;
 	struct vm_area_struct *vma = mmap_event->vma;
 	struct file *file = vma->vm_file;
 	unsigned int size;
 	char tmp[16];
 	char *buf = NULL;
 	const char *name;
-	struct pmu *pmu;
-	int ctxn;
 
 	memset(tmp, 0, sizeof(tmp));
 
@@ -4829,27 +4784,10 @@ got_name:
 
 	mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size;
 
-	rcu_read_lock();
-	list_for_each_entry_rcu(pmu, &pmus, entry) {
-		cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
-		if (cpuctx->unique_pmu != pmu)
-			goto next;
-		perf_event_mmap_ctx(&cpuctx->ctx, mmap_event,
-					vma->vm_flags & VM_EXEC);
-
-		ctxn = pmu->task_ctx_nr;
-		if (ctxn < 0)
-			goto next;
-
-		ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
-		if (ctx) {
-			perf_event_mmap_ctx(ctx, mmap_event,
-					vma->vm_flags & VM_EXEC);
-		}
-next:
-		put_cpu_ptr(pmu->pmu_cpu_context);
-	}
-	rcu_read_unlock();
+	perf_event_aux(perf_event_mmap_match,
+		       perf_event_mmap_output,
+		       mmap_event,
+		       NULL);
 
 	kfree(buf);
 }
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig
index e4c07b0692bb..70f27e89012b 100644
--- a/kernel/time/Kconfig
+++ b/kernel/time/Kconfig
@@ -12,11 +12,6 @@ config CLOCKSOURCE_WATCHDOG
 config ARCH_CLOCKSOURCE_DATA
 	bool
 
-# Platforms has a persistent clock
-config ALWAYS_USE_PERSISTENT_CLOCK
-	bool
-	default n
-
 # Timekeeping vsyscall support
 config GENERIC_TIME_VSYSCALL
 	bool
diff --git a/kernel/time/Makefile b/kernel/time/Makefile
index ff7d9d2ab504..9250130646f5 100644
--- a/kernel/time/Makefile
+++ b/kernel/time/Makefile
@@ -4,6 +4,8 @@ obj-y += timeconv.o posix-clock.o alarmtimer.o
 obj-$(CONFIG_GENERIC_CLOCKEVENTS_BUILD)		+= clockevents.o
 obj-$(CONFIG_GENERIC_CLOCKEVENTS)		+= tick-common.o
 obj-$(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)	+= tick-broadcast.o
+obj-$(CONFIG_GENERIC_SCHED_CLOCK)		+= sched_clock.o
 obj-$(CONFIG_TICK_ONESHOT)			+= tick-oneshot.o
 obj-$(CONFIG_TICK_ONESHOT)			+= tick-sched.o
 obj-$(CONFIG_TIMER_STATS)			+= timer_stats.o
+obj-$(CONFIG_DEBUG_FS)				+= timekeeping_debug.o
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index f11d83b12949..eec50fcef9e4 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -199,6 +199,13 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
 
 }
 
+ktime_t alarm_expires_remaining(const struct alarm *alarm)
+{
+	struct alarm_base *base = &alarm_bases[alarm->type];
+	return ktime_sub(alarm->node.expires, base->gettime());
+}
+EXPORT_SYMBOL_GPL(alarm_expires_remaining);
+
 #ifdef CONFIG_RTC_CLASS
 /**
  * alarmtimer_suspend - Suspend time callback
@@ -303,9 +310,10 @@ void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
 	alarm->type = type;
 	alarm->state = ALARMTIMER_STATE_INACTIVE;
 }
+EXPORT_SYMBOL_GPL(alarm_init);
 
 /**
- * alarm_start - Sets an alarm to fire
+ * alarm_start - Sets an absolute alarm to fire
  * @alarm: ptr to alarm to set
  * @start: time to run the alarm
  */
@@ -323,6 +331,34 @@ int alarm_start(struct alarm *alarm, ktime_t start)
 	spin_unlock_irqrestore(&base->lock, flags);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(alarm_start);
+
+/**
+ * alarm_start_relative - Sets a relative alarm to fire
+ * @alarm: ptr to alarm to set
+ * @start: time relative to now to run the alarm
+ */
+int alarm_start_relative(struct alarm *alarm, ktime_t start)
+{
+	struct alarm_base *base = &alarm_bases[alarm->type];
+
+	start = ktime_add(start, base->gettime());
+	return alarm_start(alarm, start);
+}
+EXPORT_SYMBOL_GPL(alarm_start_relative);
+
+void alarm_restart(struct alarm *alarm)
+{
+	struct alarm_base *base = &alarm_bases[alarm->type];
+	unsigned long flags;
+
+	spin_lock_irqsave(&base->lock, flags);
+	hrtimer_set_expires(&alarm->timer, alarm->node.expires);
+	hrtimer_restart(&alarm->timer);
+	alarmtimer_enqueue(base, alarm);
+	spin_unlock_irqrestore(&base->lock, flags);
+}
+EXPORT_SYMBOL_GPL(alarm_restart);
 
 /**
  * alarm_try_to_cancel - Tries to cancel an alarm timer
@@ -344,6 +380,7 @@ int alarm_try_to_cancel(struct alarm *alarm)
 	spin_unlock_irqrestore(&base->lock, flags);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(alarm_try_to_cancel);
 
 
 /**
@@ -361,6 +398,7 @@ int alarm_cancel(struct alarm *alarm)
 		cpu_relax();
 	}
 }
+EXPORT_SYMBOL_GPL(alarm_cancel);
 
 
 u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval)
@@ -393,8 +431,15 @@ u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval)
 	alarm->node.expires = ktime_add(alarm->node.expires, interval);
 	return overrun;
 }
+EXPORT_SYMBOL_GPL(alarm_forward);
 
+u64 alarm_forward_now(struct alarm *alarm, ktime_t interval)
+{
+	struct alarm_base *base = &alarm_bases[alarm->type];
 
+	return alarm_forward(alarm, base->gettime(), interval);
+}
+EXPORT_SYMBOL_GPL(alarm_forward_now);
 
 
 /**
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index c6d6400ee137..38959c866789 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -15,20 +15,23 @@
 #include <linux/hrtimer.h>
 #include <linux/init.h>
 #include <linux/module.h>
-#include <linux/notifier.h>
 #include <linux/smp.h>
+#include <linux/device.h>
 
 #include "tick-internal.h"
 
 /* The registered clock event devices */
 static LIST_HEAD(clockevent_devices);
 static LIST_HEAD(clockevents_released);
-
-/* Notification for clock events */
-static RAW_NOTIFIER_HEAD(clockevents_chain);
-
 /* Protection for the above */
 static DEFINE_RAW_SPINLOCK(clockevents_lock);
+/* Protection for unbind operations */
+static DEFINE_MUTEX(clockevents_mutex);
+
+struct ce_unbind {
+	struct clock_event_device *ce;
+	int res;
+};
 
 /**
  * clockevents_delta2ns - Convert a latch value (device ticks) to nanoseconds
@@ -232,47 +235,107 @@ int clockevents_program_event(struct clock_event_device *dev, ktime_t expires,
 	return (rc && force) ? clockevents_program_min_delta(dev) : rc;
 }
 
-/**
- * clockevents_register_notifier - register a clock events change listener
+/*
+ * Called after a notify add to make devices available which were
+ * released from the notifier call.
  */
-int clockevents_register_notifier(struct notifier_block *nb)
+static void clockevents_notify_released(void)
 {
-	unsigned long flags;
-	int ret;
+	struct clock_event_device *dev;
 
-	raw_spin_lock_irqsave(&clockevents_lock, flags);
-	ret = raw_notifier_chain_register(&clockevents_chain, nb);
-	raw_spin_unlock_irqrestore(&clockevents_lock, flags);
+	while (!list_empty(&clockevents_released)) {
+		dev = list_entry(clockevents_released.next,
+				 struct clock_event_device, list);
+		list_del(&dev->list);
+		list_add(&dev->list, &clockevent_devices);
+		tick_check_new_device(dev);
+	}
+}
 
-	return ret;
+/*
+ * Try to install a replacement clock event device
+ */
+static int clockevents_replace(struct clock_event_device *ced)
+{
+	struct clock_event_device *dev, *newdev = NULL;
+
+	list_for_each_entry(dev, &clockevent_devices, list) {
+		if (dev == ced || dev->mode != CLOCK_EVT_MODE_UNUSED)
+			continue;
+
+		if (!tick_check_replacement(newdev, dev))
+			continue;
+
+		if (!try_module_get(dev->owner))
+			continue;
+
+		if (newdev)
+			module_put(newdev->owner);
+		newdev = dev;
+	}
+	if (newdev) {
+		tick_install_replacement(newdev);
+		list_del_init(&ced->list);
+	}
+	return newdev ? 0 : -EBUSY;
 }
 
 /*
- * Notify about a clock event change. Called with clockevents_lock
- * held.
+ * Called with clockevents_mutex and clockevents_lock held
  */
-static void clockevents_do_notify(unsigned long reason, void *dev)
+static int __clockevents_try_unbind(struct clock_event_device *ced, int cpu)
 {
-	raw_notifier_call_chain(&clockevents_chain, reason, dev);
+	/* Fast track. Device is unused */
+	if (ced->mode == CLOCK_EVT_MODE_UNUSED) {
+		list_del_init(&ced->list);
+		return 0;
+	}
+
+	return ced == per_cpu(tick_cpu_device, cpu).evtdev ? -EAGAIN : -EBUSY;
 }
 
 /*
- * Called after a notify add to make devices available which were
- * released from the notifier call.
+ * SMP function call to unbind a device
  */
-static void clockevents_notify_released(void)
+static void __clockevents_unbind(void *arg)
 {
-	struct clock_event_device *dev;
+	struct ce_unbind *cu = arg;
+	int res;
+
+	raw_spin_lock(&clockevents_lock);
+	res = __clockevents_try_unbind(cu->ce, smp_processor_id());
+	if (res == -EAGAIN)
+		res = clockevents_replace(cu->ce);
+	cu->res = res;
+	raw_spin_unlock(&clockevents_lock);
+}
 
-	while (!list_empty(&clockevents_released)) {
-		dev = list_entry(clockevents_released.next,
-				 struct clock_event_device, list);
-		list_del(&dev->list);
-		list_add(&dev->list, &clockevent_devices);
-		clockevents_do_notify(CLOCK_EVT_NOTIFY_ADD, dev);
-	}
+/*
+ * Issues smp function call to unbind a per cpu device. Called with
+ * clockevents_mutex held.
+ */
+static int clockevents_unbind(struct clock_event_device *ced, int cpu)
+{
+	struct ce_unbind cu = { .ce = ced, .res = -ENODEV };
+
+	smp_call_function_single(cpu, __clockevents_unbind, &cu, 1);
+	return cu.res;
 }
 
+/*
+ * Unbind a clockevents device.
+ */
+int clockevents_unbind_device(struct clock_event_device *ced, int cpu)
+{
+	int ret;
+
+	mutex_lock(&clockevents_mutex);
+	ret = clockevents_unbind(ced, cpu);
+	mutex_unlock(&clockevents_mutex);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(clockevents_unbind);
+
 /**
  * clockevents_register_device - register a clock event device
  * @dev:	device to register
@@ -290,7 +353,7 @@ void clockevents_register_device(struct clock_event_device *dev)
 	raw_spin_lock_irqsave(&clockevents_lock, flags);
 
 	list_add(&dev->list, &clockevent_devices);
-	clockevents_do_notify(CLOCK_EVT_NOTIFY_ADD, dev);
+	tick_check_new_device(dev);
 	clockevents_notify_released();
 
 	raw_spin_unlock_irqrestore(&clockevents_lock, flags);
@@ -386,6 +449,7 @@ void clockevents_exchange_device(struct clock_event_device *old,
 	 * released list and do a notify add later.
 	 */
 	if (old) {
+		module_put(old->owner);
 		clockevents_set_mode(old, CLOCK_EVT_MODE_UNUSED);
 		list_del(&old->list);
 		list_add(&old->list, &clockevents_released);
@@ -433,10 +497,36 @@ void clockevents_notify(unsigned long reason, void *arg)
 	int cpu;
 
 	raw_spin_lock_irqsave(&clockevents_lock, flags);
-	clockevents_do_notify(reason, arg);
 
 	switch (reason) {
+	case CLOCK_EVT_NOTIFY_BROADCAST_ON:
+	case CLOCK_EVT_NOTIFY_BROADCAST_OFF:
+	case CLOCK_EVT_NOTIFY_BROADCAST_FORCE:
+		tick_broadcast_on_off(reason, arg);
+		break;
+
+	case CLOCK_EVT_NOTIFY_BROADCAST_ENTER:
+	case CLOCK_EVT_NOTIFY_BROADCAST_EXIT:
+		tick_broadcast_oneshot_control(reason);
+		break;
+
+	case CLOCK_EVT_NOTIFY_CPU_DYING:
+		tick_handover_do_timer(arg);
+		break;
+
+	case CLOCK_EVT_NOTIFY_SUSPEND:
+		tick_suspend();
+		tick_suspend_broadcast();
+		break;
+
+	case CLOCK_EVT_NOTIFY_RESUME:
+		tick_resume();
+		break;
+
 	case CLOCK_EVT_NOTIFY_CPU_DEAD:
+		tick_shutdown_broadcast_oneshot(arg);
+		tick_shutdown_broadcast(arg);
+		tick_shutdown(arg);
 		/*
 		 * Unregister the clock event devices which were
 		 * released from the users in the notify chain.
@@ -462,4 +552,123 @@ void clockevents_notify(unsigned long reason, void *arg)
 	raw_spin_unlock_irqrestore(&clockevents_lock, flags);
 }
 EXPORT_SYMBOL_GPL(clockevents_notify);
+
+#ifdef CONFIG_SYSFS
+struct bus_type clockevents_subsys = {
+	.name		= "clockevents",
+	.dev_name       = "clockevent",
+};
+
+static DEFINE_PER_CPU(struct device, tick_percpu_dev);
+static struct tick_device *tick_get_tick_dev(struct device *dev);
+
+static ssize_t sysfs_show_current_tick_dev(struct device *dev,
+					   struct device_attribute *attr,
+					   char *buf)
+{
+	struct tick_device *td;
+	ssize_t count = 0;
+
+	raw_spin_lock_irq(&clockevents_lock);
+	td = tick_get_tick_dev(dev);
+	if (td && td->evtdev)
+		count = snprintf(buf, PAGE_SIZE, "%s\n", td->evtdev->name);
+	raw_spin_unlock_irq(&clockevents_lock);
+	return count;
+}
+static DEVICE_ATTR(current_device, 0444, sysfs_show_current_tick_dev, NULL);
+
+/* We don't support the abomination of removable broadcast devices */
+static ssize_t sysfs_unbind_tick_dev(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	char name[CS_NAME_LEN];
+	size_t ret = sysfs_get_uname(buf, name, count);
+	struct clock_event_device *ce;
+
+	if (ret < 0)
+		return ret;
+
+	ret = -ENODEV;
+	mutex_lock(&clockevents_mutex);
+	raw_spin_lock_irq(&clockevents_lock);
+	list_for_each_entry(ce, &clockevent_devices, list) {
+		if (!strcmp(ce->name, name)) {
+			ret = __clockevents_try_unbind(ce, dev->id);
+			break;
+		}
+	}
+	raw_spin_unlock_irq(&clockevents_lock);
+	/*
+	 * We hold clockevents_mutex, so ce can't go away
+	 */
+	if (ret == -EAGAIN)
+		ret = clockevents_unbind(ce, dev->id);
+	mutex_unlock(&clockevents_mutex);
+	return ret ? ret : count;
+}
+static DEVICE_ATTR(unbind_device, 0200, NULL, sysfs_unbind_tick_dev);
+
+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+static struct device tick_bc_dev = {
+	.init_name	= "broadcast",
+	.id		= 0,
+	.bus		= &clockevents_subsys,
+};
+
+static struct tick_device *tick_get_tick_dev(struct device *dev)
+{
+	return dev == &tick_bc_dev ? tick_get_broadcast_device() :
+		&per_cpu(tick_cpu_device, dev->id);
+}
+
+static __init int tick_broadcast_init_sysfs(void)
+{
+	int err = device_register(&tick_bc_dev);
+
+	if (!err)
+		err = device_create_file(&tick_bc_dev, &dev_attr_current_device);
+	return err;
+}
+#else
+static struct tick_device *tick_get_tick_dev(struct device *dev)
+{
+	return &per_cpu(tick_cpu_device, dev->id);
+}
+static inline int tick_broadcast_init_sysfs(void) { return 0; }
 #endif
+
+static int __init tick_init_sysfs(void)
+{
+	int cpu;
+
+	for_each_possible_cpu(cpu) {
+		struct device *dev = &per_cpu(tick_percpu_dev, cpu);
+		int err;
+
+		dev->id = cpu;
+		dev->bus = &clockevents_subsys;
+		err = device_register(dev);
+		if (!err)
+			err = device_create_file(dev, &dev_attr_current_device);
+		if (!err)
+			err = device_create_file(dev, &dev_attr_unbind_device);
+		if (err)
+			return err;
+	}
+	return tick_broadcast_init_sysfs();
+}
+
+static int __init clockevents_init_sysfs(void)
+{
+	int err = subsys_system_register(&clockevents_subsys, NULL);
+
+	if (!err)
+		err = tick_init_sysfs();
+	return err;
+}
+device_initcall(clockevents_init_sysfs);
+#endif /* SYSFS */
+
+#endif /* GENERIC_CLOCK_EVENTS */
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index c9583382141a..e713ef7d19a7 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -31,6 +31,8 @@
 #include <linux/tick.h>
 #include <linux/kthread.h>
 
+#include "tick-internal.h"
+
 void timecounter_init(struct timecounter *tc,
 		      const struct cyclecounter *cc,
 		      u64 start_tstamp)
@@ -174,7 +176,7 @@ clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 maxsec)
 static struct clocksource *curr_clocksource;
 static LIST_HEAD(clocksource_list);
 static DEFINE_MUTEX(clocksource_mutex);
-static char override_name[32];
+static char override_name[CS_NAME_LEN];
 static int finished_booting;
 
 #ifdef CONFIG_CLOCKSOURCE_WATCHDOG
@@ -388,28 +390,17 @@ static void clocksource_enqueue_watchdog(struct clocksource *cs)
 
 static void clocksource_dequeue_watchdog(struct clocksource *cs)
 {
-	struct clocksource *tmp;
 	unsigned long flags;
 
 	spin_lock_irqsave(&watchdog_lock, flags);
-	if (cs->flags & CLOCK_SOURCE_MUST_VERIFY) {
-		/* cs is a watched clocksource. */
-		list_del_init(&cs->wd_list);
-	} else if (cs == watchdog) {
-		/* Reset watchdog cycles */
-		clocksource_reset_watchdog();
-		/* Current watchdog is removed. Find an alternative. */
-		watchdog = NULL;
-		list_for_each_entry(tmp, &clocksource_list, list) {
-			if (tmp == cs || tmp->flags & CLOCK_SOURCE_MUST_VERIFY)
-				continue;
-			if (!watchdog || tmp->rating > watchdog->rating)
-				watchdog = tmp;
+	if (cs != watchdog) {
+		if (cs->flags & CLOCK_SOURCE_MUST_VERIFY) {
+			/* cs is a watched clocksource. */
+			list_del_init(&cs->wd_list);
+			/* Check if the watchdog timer needs to be stopped. */
+			clocksource_stop_watchdog();
 		}
 	}
-	cs->flags &= ~CLOCK_SOURCE_WATCHDOG;
-	/* Check if the watchdog timer needs to be stopped. */
-	clocksource_stop_watchdog();
 	spin_unlock_irqrestore(&watchdog_lock, flags);
 }
 
@@ -439,6 +430,11 @@ static int clocksource_watchdog_kthread(void *data)
 	return 0;
 }
 
+static bool clocksource_is_watchdog(struct clocksource *cs)
+{
+	return cs == watchdog;
+}
+
 #else /* CONFIG_CLOCKSOURCE_WATCHDOG */
 
 static void clocksource_enqueue_watchdog(struct clocksource *cs)
@@ -450,6 +446,7 @@ static void clocksource_enqueue_watchdog(struct clocksource *cs)
 static inline void clocksource_dequeue_watchdog(struct clocksource *cs) { }
 static inline void clocksource_resume_watchdog(void) { }
 static inline int clocksource_watchdog_kthread(void *data) { return 0; }
+static bool clocksource_is_watchdog(struct clocksource *cs) { return false; }
 
 #endif /* CONFIG_CLOCKSOURCE_WATCHDOG */
 
@@ -553,24 +550,42 @@ static u64 clocksource_max_deferment(struct clocksource *cs)
 
 #ifndef CONFIG_ARCH_USES_GETTIMEOFFSET
 
-/**
- * clocksource_select - Select the best clocksource available
- *
- * Private function. Must hold clocksource_mutex when called.
- *
- * Select the clocksource with the best rating, or the clocksource,
- * which is selected by userspace override.
- */
-static void clocksource_select(void)
+static struct clocksource *clocksource_find_best(bool oneshot, bool skipcur)
 {
-	struct clocksource *best, *cs;
+	struct clocksource *cs;
 
 	if (!finished_booting || list_empty(&clocksource_list))
+		return NULL;
+
+	/*
+	 * We pick the clocksource with the highest rating. If oneshot
+	 * mode is active, we pick the highres valid clocksource with
+	 * the best rating.
+	 */
+	list_for_each_entry(cs, &clocksource_list, list) {
+		if (skipcur && cs == curr_clocksource)
+			continue;
+		if (oneshot && !(cs->flags & CLOCK_SOURCE_VALID_FOR_HRES))
+			continue;
+		return cs;
+	}
+	return NULL;
+}
+
+static void __clocksource_select(bool skipcur)
+{
+	bool oneshot = tick_oneshot_mode_active();
+	struct clocksource *best, *cs;
+
+	/* Find the best suitable clocksource */
+	best = clocksource_find_best(oneshot, skipcur);
+	if (!best)
 		return;
-	/* First clocksource on the list has the best rating. */
-	best = list_first_entry(&clocksource_list, struct clocksource, list);
+
 	/* Check for the override clocksource. */
 	list_for_each_entry(cs, &clocksource_list, list) {
+		if (skipcur && cs == curr_clocksource)
+			continue;
 		if (strcmp(cs->name, override_name) != 0)
 			continue;
 		/*
@@ -578,8 +593,7 @@ static void clocksource_select(void)
 		 * capable clocksource if the tick code is in oneshot
 		 * mode (highres or nohz)
 		 */
-		if (!(cs->flags & CLOCK_SOURCE_VALID_FOR_HRES) &&
-		    tick_oneshot_mode_active()) {
+		if (!(cs->flags & CLOCK_SOURCE_VALID_FOR_HRES) && oneshot) {
 			/* Override clocksource cannot be used. */
 			printk(KERN_WARNING "Override clocksource %s is not "
 			       "HRT compatible. Cannot switch while in "
@@ -590,16 +604,35 @@ static void clocksource_select(void)
 			best = cs;
 		break;
 	}
-	if (curr_clocksource != best) {
-		printk(KERN_INFO "Switching to clocksource %s\n", best->name);
+
+	if (curr_clocksource != best && !timekeeping_notify(best)) {
+		pr_info("Switched to clocksource %s\n", best->name);
 		curr_clocksource = best;
-		timekeeping_notify(curr_clocksource);
 	}
 }
 
+/**
+ * clocksource_select - Select the best clocksource available
+ *
+ * Private function. Must hold clocksource_mutex when called.
+ *
+ * Select the clocksource with the best rating, or the clocksource,
+ * which is selected by userspace override.
+ */
+static void clocksource_select(void)
+{
+	return __clocksource_select(false);
+}
+
+static void clocksource_select_fallback(void)
+{
+	return __clocksource_select(true);
+}
+
 #else /* !CONFIG_ARCH_USES_GETTIMEOFFSET */
 
 static inline void clocksource_select(void) { }
+static inline void clocksource_select_fallback(void) { }
 
 #endif
 
@@ -772,17 +805,42 @@ void clocksource_change_rating(struct clocksource *cs, int rating)
 }
 EXPORT_SYMBOL(clocksource_change_rating);
 
+/*
+ * Unbind clocksource @cs. Called with clocksource_mutex held
+ */
+static int clocksource_unbind(struct clocksource *cs)
+{
+	/*
+	 * I really can't convince myself to support this on hardware
+	 * designed by lobotomized monkeys.
+	 */
+	if (clocksource_is_watchdog(cs))
+		return -EBUSY;
+
+	if (cs == curr_clocksource) {
+		/* Select and try to install a replacement clock source */
+		clocksource_select_fallback();
+		if (curr_clocksource == cs)
+			return -EBUSY;
+	}
+	clocksource_dequeue_watchdog(cs);
+	list_del_init(&cs->list);
+	return 0;
+}
+
 /**
  * clocksource_unregister - remove a registered clocksource
  * @cs:	clocksource to be unregistered
  */
-void clocksource_unregister(struct clocksource *cs)
+int clocksource_unregister(struct clocksource *cs)
 {
+	int ret = 0;
+
 	mutex_lock(&clocksource_mutex);
-	clocksource_dequeue_watchdog(cs);
-	list_del(&cs->list);
-	clocksource_select();
+	if (!list_empty(&cs->list))
+		ret = clocksource_unbind(cs);
 	mutex_unlock(&clocksource_mutex);
+	return ret;
 }
 EXPORT_SYMBOL(clocksource_unregister);
 
@@ -808,6 +866,23 @@ sysfs_show_current_clocksources(struct device *dev,
 	return count;
 }
 
+size_t sysfs_get_uname(const char *buf, char *dst, size_t cnt)
+{
+	size_t ret = cnt;
+
+	/* strings from sysfs write are not 0 terminated! */
+	if (!cnt || cnt >= CS_NAME_LEN)
+		return -EINVAL;
+
+	/* strip of \n: */
+	if (buf[cnt-1] == '\n')
+		cnt--;
+	if (cnt > 0)
+		memcpy(dst, buf, cnt);
+	dst[cnt] = 0;
+	return ret;
+}
+
 /**
  * sysfs_override_clocksource - interface for manually overriding clocksource
  * @dev:	unused
@@ -822,22 +897,13 @@ static ssize_t sysfs_override_clocksource(struct device *dev,
 					  struct device_attribute *attr,
 					  const char *buf, size_t count)
 {
-	size_t ret = count;
-
-	/* strings from sysfs write are not 0 terminated! */
-	if (count >= sizeof(override_name))
-		return -EINVAL;
-
-	/* strip of \n: */
-	if (buf[count-1] == '\n')
-		count--;
+	size_t ret;
 
 	mutex_lock(&clocksource_mutex);
 
-	if (count > 0)
-		memcpy(override_name, buf, count);
-	override_name[count] = 0;
-	clocksource_select();
+	ret = sysfs_get_uname(buf, override_name, count);
+	if (ret >= 0)
+		clocksource_select();
 
 	mutex_unlock(&clocksource_mutex);
 
@@ -845,6 +911,40 @@ static ssize_t sysfs_override_clocksource(struct device *dev,
 }
 
 /**
+ * sysfs_unbind_current_clocksource - interface for manually unbinding clocksource
+ * @dev:	unused
+ * @attr:	unused
+ * @buf:	unused
+ * @count:	length of buffer
+ *
+ * Takes input from sysfs interface for manually unbinding a clocksource.
+ */
+static ssize_t sysfs_unbind_clocksource(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct clocksource *cs;
+	char name[CS_NAME_LEN];
+	size_t ret;
+
+	ret = sysfs_get_uname(buf, name, count);
+	if (ret < 0)
+		return ret;
+
+	ret = -ENODEV;
+	mutex_lock(&clocksource_mutex);
+	list_for_each_entry(cs, &clocksource_list, list) {
+		if (strcmp(cs->name, name))
+			continue;
+		ret = clocksource_unbind(cs);
+		break;
+	}
+	mutex_unlock(&clocksource_mutex);
+
+	return ret ? ret : count;
+}
+
+/**
  * sysfs_show_available_clocksources - sysfs interface for listing clocksource
  * @dev:	unused
  * @attr:	unused
@@ -886,6 +986,8 @@ sysfs_show_available_clocksources(struct device *dev,
 static DEVICE_ATTR(current_clocksource, 0644, sysfs_show_current_clocksources,
 		   sysfs_override_clocksource);
 
+static DEVICE_ATTR(unbind_clocksource, 0200, NULL, sysfs_unbind_clocksource);
+
 static DEVICE_ATTR(available_clocksource, 0444,
 		   sysfs_show_available_clocksources, NULL);
 
@@ -910,6 +1012,9 @@ static int __init init_clocksource_sysfs(void)
 				&device_clocksource,
 				&dev_attr_current_clocksource);
 	if (!error)
+		error = device_create_file(&device_clocksource,
+					   &dev_attr_unbind_clocksource);
+	if (!error)
 		error = device_create_file(
 				&device_clocksource,
 				&dev_attr_available_clocksource);
diff --git a/kernel/time/sched_clock.c b/kernel/time/sched_clock.c
new file mode 100644
index 000000000000..a326f27d7f09
--- /dev/null
+++ b/kernel/time/sched_clock.c
@@ -0,0 +1,212 @@
+/*
+ * sched_clock.c: support for extending counters to full 64-bit ns counter
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/clocksource.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/moduleparam.h>
+#include <linux/sched.h>
+#include <linux/syscore_ops.h>
+#include <linux/timer.h>
+#include <linux/sched_clock.h>
+
+struct clock_data {
+	u64 epoch_ns;
+	u32 epoch_cyc;
+	u32 epoch_cyc_copy;
+	unsigned long rate;
+	u32 mult;
+	u32 shift;
+	bool suspended;
+};
+
+static void sched_clock_poll(unsigned long wrap_ticks);
+static DEFINE_TIMER(sched_clock_timer, sched_clock_poll, 0, 0);
+static int irqtime = -1;
+
+core_param(irqtime, irqtime, int, 0400);
+
+static struct clock_data cd = {
+	.mult	= NSEC_PER_SEC / HZ,
+};
+
+static u32 __read_mostly sched_clock_mask = 0xffffffff;
+
+static u32 notrace jiffy_sched_clock_read(void)
+{
+	return (u32)(jiffies - INITIAL_JIFFIES);
+}
+
+static u32 __read_mostly (*read_sched_clock)(void) = jiffy_sched_clock_read;
+
+static inline u64 notrace cyc_to_ns(u64 cyc, u32 mult, u32 shift)
+{
+	return (cyc * mult) >> shift;
+}
+
+static unsigned long long notrace sched_clock_32(void)
+{
+	u64 epoch_ns;
+	u32 epoch_cyc;
+	u32 cyc;
+
+	if (cd.suspended)
+		return cd.epoch_ns;
+
+	/*
+	 * Load the epoch_cyc and epoch_ns atomically.  We do this by
+	 * ensuring that we always write epoch_cyc, epoch_ns and
+	 * epoch_cyc_copy in strict order, and read them in strict order.
+	 * If epoch_cyc and epoch_cyc_copy are not equal, then we're in
+	 * the middle of an update, and we should repeat the load.
+	 */
+	do {
+		epoch_cyc = cd.epoch_cyc;
+		smp_rmb();
+		epoch_ns = cd.epoch_ns;
+		smp_rmb();
+	} while (epoch_cyc != cd.epoch_cyc_copy);
+
+	cyc = read_sched_clock();
+	cyc = (cyc - epoch_cyc) & sched_clock_mask;
+	return epoch_ns + cyc_to_ns(cyc, cd.mult, cd.shift);
+}
+
+/*
+ * Atomically update the sched_clock epoch.
+ */
+static void notrace update_sched_clock(void)
+{
+	unsigned long flags;
+	u32 cyc;
+	u64 ns;
+
+	cyc = read_sched_clock();
+	ns = cd.epoch_ns +
+		cyc_to_ns((cyc - cd.epoch_cyc) & sched_clock_mask,
+			  cd.mult, cd.shift);
+	/*
+	 * Write epoch_cyc and epoch_ns in a way that the update is
+	 * detectable in cyc_to_fixed_sched_clock().
+	 */
+	raw_local_irq_save(flags);
+	cd.epoch_cyc_copy = cyc;
+	smp_wmb();
+	cd.epoch_ns = ns;
+	smp_wmb();
+	cd.epoch_cyc = cyc;
+	raw_local_irq_restore(flags);
+}
+
+static void sched_clock_poll(unsigned long wrap_ticks)
+{
+	mod_timer(&sched_clock_timer, round_jiffies(jiffies + wrap_ticks));
+	update_sched_clock();
+}
+
+void __init setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate)
+{
+	unsigned long r, w;
+	u64 res, wrap;
+	char r_unit;
+
+	if (cd.rate > rate)
+		return;
+
+	BUG_ON(bits > 32);
+	WARN_ON(!irqs_disabled());
+	read_sched_clock = read;
+	sched_clock_mask = (1 << bits) - 1;
+	cd.rate = rate;
+
+	/* calculate the mult/shift to convert counter ticks to ns. */
+	clocks_calc_mult_shift(&cd.mult, &cd.shift, rate, NSEC_PER_SEC, 0);
+
+	r = rate;
+	if (r >= 4000000) {
+		r /= 1000000;
+		r_unit = 'M';
+	} else if (r >= 1000) {
+		r /= 1000;
+		r_unit = 'k';
+	} else
+		r_unit = ' ';
+
+	/* calculate how many ns until we wrap */
+	wrap = cyc_to_ns((1ULL << bits) - 1, cd.mult, cd.shift);
+	do_div(wrap, NSEC_PER_MSEC);
+	w = wrap;
+
+	/* calculate the ns resolution of this counter */
+	res = cyc_to_ns(1ULL, cd.mult, cd.shift);
+	pr_info("sched_clock: %u bits at %lu%cHz, resolution %lluns, wraps every %lums\n",
+		bits, r, r_unit, res, w);
+
+	/*
+	 * Start the timer to keep sched_clock() properly updated and
+	 * sets the initial epoch.
+	 */
+	sched_clock_timer.data = msecs_to_jiffies(w - (w / 10));
+	update_sched_clock();
+
+	/*
+	 * Ensure that sched_clock() starts off at 0ns
+	 */
+	cd.epoch_ns = 0;
+
+	/* Enable IRQ time accounting if we have a fast enough sched_clock */
+	if (irqtime > 0 || (irqtime == -1 && rate >= 1000000))
+		enable_sched_clock_irqtime();
+
+	pr_debug("Registered %pF as sched_clock source\n", read);
+}
+
+unsigned long long __read_mostly (*sched_clock_func)(void) = sched_clock_32;
+
+unsigned long long notrace sched_clock(void)
+{
+	return sched_clock_func();
+}
+
+void __init sched_clock_postinit(void)
+{
+	/*
+	 * If no sched_clock function has been provided at that point,
+	 * make it the final one one.
+	 */
+	if (read_sched_clock == jiffy_sched_clock_read)
+		setup_sched_clock(jiffy_sched_clock_read, 32, HZ);
+
+	sched_clock_poll(sched_clock_timer.data);
+}
+
+static int sched_clock_suspend(void)
+{
+	sched_clock_poll(sched_clock_timer.data);
+	cd.suspended = true;
+	return 0;
+}
+
+static void sched_clock_resume(void)
+{
+	cd.epoch_cyc = read_sched_clock();
+	cd.epoch_cyc_copy = cd.epoch_cyc;
+	cd.suspended = false;
+}
+
+static struct syscore_ops sched_clock_ops = {
+	.suspend = sched_clock_suspend,
+	.resume = sched_clock_resume,
+};
+
+static int __init sched_clock_syscore_init(void)
+{
+	register_syscore_ops(&sched_clock_ops);
+	return 0;
+}
+device_initcall(sched_clock_syscore_init);
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 206bbfb34e09..d067c01586f5 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -19,6 +19,7 @@
 #include <linux/profile.h>
 #include <linux/sched.h>
 #include <linux/smp.h>
+#include <linux/module.h>
 
 #include "tick-internal.h"
 
@@ -64,17 +65,34 @@ static void tick_broadcast_start_periodic(struct clock_event_device *bc)
 /*
  * Check, if the device can be utilized as broadcast device:
  */
-int tick_check_broadcast_device(struct clock_event_device *dev)
+static bool tick_check_broadcast_device(struct clock_event_device *curdev,
+					struct clock_event_device *newdev)
+{
+	if ((newdev->features & CLOCK_EVT_FEAT_DUMMY) ||
+	    (newdev->features & CLOCK_EVT_FEAT_C3STOP))
+		return false;
+
+	if (tick_broadcast_device.mode == TICKDEV_MODE_ONESHOT &&
+	    !(newdev->features & CLOCK_EVT_FEAT_ONESHOT))
+		return false;
+
+	return !curdev || newdev->rating > curdev->rating;
+}
+
+/*
+ * Conditionally install/replace broadcast device
+ */
+void tick_install_broadcast_device(struct clock_event_device *dev)
 {
 	struct clock_event_device *cur = tick_broadcast_device.evtdev;
 
-	if ((dev->features & CLOCK_EVT_FEAT_DUMMY) ||
-	    (tick_broadcast_device.evtdev &&
-	     tick_broadcast_device.evtdev->rating >= dev->rating) ||
-	     (dev->features & CLOCK_EVT_FEAT_C3STOP))
-		return 0;
+	if (!tick_check_broadcast_device(cur, dev))
+		return;
+
+	if (!try_module_get(dev->owner))
+		return;
 
-	clockevents_exchange_device(tick_broadcast_device.evtdev, dev);
+	clockevents_exchange_device(cur, dev);
 	if (cur)
 		cur->event_handler = clockevents_handle_noop;
 	tick_broadcast_device.evtdev = dev;
@@ -90,7 +108,6 @@ int tick_check_broadcast_device(struct clock_event_device *dev)
 	 */
 	if (dev->features & CLOCK_EVT_FEAT_ONESHOT)
 		tick_clock_notify();
-	return 1;
 }
 
 /*
@@ -786,11 +803,11 @@ bool tick_broadcast_oneshot_available(void)
 
 void __init tick_broadcast_init(void)
 {
-	alloc_cpumask_var(&tick_broadcast_mask, GFP_NOWAIT);
-	alloc_cpumask_var(&tmpmask, GFP_NOWAIT);
+	zalloc_cpumask_var(&tick_broadcast_mask, GFP_NOWAIT);
+	zalloc_cpumask_var(&tmpmask, GFP_NOWAIT);
 #ifdef CONFIG_TICK_ONESHOT
-	alloc_cpumask_var(&tick_broadcast_oneshot_mask, GFP_NOWAIT);
-	alloc_cpumask_var(&tick_broadcast_pending_mask, GFP_NOWAIT);
-	alloc_cpumask_var(&tick_broadcast_force_mask, GFP_NOWAIT);
+	zalloc_cpumask_var(&tick_broadcast_oneshot_mask, GFP_NOWAIT);
+	zalloc_cpumask_var(&tick_broadcast_pending_mask, GFP_NOWAIT);
+	zalloc_cpumask_var(&tick_broadcast_force_mask, GFP_NOWAIT);
 #endif
 }
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index 5d3fb100bc06..edd45f64162f 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -18,6 +18,7 @@
 #include <linux/percpu.h>
 #include <linux/profile.h>
 #include <linux/sched.h>
+#include <linux/module.h>
 
 #include <asm/irq_regs.h>
 
@@ -33,7 +34,6 @@ DEFINE_PER_CPU(struct tick_device, tick_cpu_device);
 ktime_t tick_next_period;
 ktime_t tick_period;
 int tick_do_timer_cpu __read_mostly = TICK_DO_TIMER_BOOT;
-static DEFINE_RAW_SPINLOCK(tick_device_lock);
 
 /*
  * Debugging: see timer_list.c
@@ -205,17 +205,75 @@ static void tick_setup_device(struct tick_device *td,
 		tick_setup_oneshot(newdev, handler, next_event);
 }
 
+void tick_install_replacement(struct clock_event_device *newdev)
+{
+	struct tick_device *td = &__get_cpu_var(tick_cpu_device);
+	int cpu = smp_processor_id();
+
+	clockevents_exchange_device(td->evtdev, newdev);
+	tick_setup_device(td, newdev, cpu, cpumask_of(cpu));
+	if (newdev->features & CLOCK_EVT_FEAT_ONESHOT)
+		tick_oneshot_notify();
+}
+
+static bool tick_check_percpu(struct clock_event_device *curdev,
+			      struct clock_event_device *newdev, int cpu)
+{
+	if (!cpumask_test_cpu(cpu, newdev->cpumask))
+		return false;
+	if (cpumask_equal(newdev->cpumask, cpumask_of(cpu)))
+		return true;
+	/* Check if irq affinity can be set */
+	if (newdev->irq >= 0 && !irq_can_set_affinity(newdev->irq))
+		return false;
+	/* Prefer an existing cpu local device */
+	if (curdev && cpumask_equal(curdev->cpumask, cpumask_of(cpu)))
+		return false;
+	return true;
+}
+
+static bool tick_check_preferred(struct clock_event_device *curdev,
+				 struct clock_event_device *newdev)
+{
+	/* Prefer oneshot capable device */
+	if (!(newdev->features & CLOCK_EVT_FEAT_ONESHOT)) {
+		if (curdev && (curdev->features & CLOCK_EVT_FEAT_ONESHOT))
+			return false;
+		if (tick_oneshot_mode_active())
+			return false;
+	}
+
+	/*
+	 * Use the higher rated one, but prefer a CPU local device with a lower
+	 * rating than a non-CPU local device
+	 */
+	return !curdev ||
+		newdev->rating > curdev->rating ||
+	       !cpumask_equal(curdev->cpumask, newdev->cpumask);
+}
+
+/*
+ * Check whether the new device is a better fit than curdev. curdev
+ * can be NULL !
+ */
+bool tick_check_replacement(struct clock_event_device *curdev,
+			    struct clock_event_device *newdev)
+{
+	if (tick_check_percpu(curdev, newdev, smp_processor_id()))
+		return false;
+
+	return tick_check_preferred(curdev, newdev);
+}
+
 /*
- * Check, if the new registered device should be used.
+ * Check, if the new registered device should be used. Called with
+ * clockevents_lock held and interrupts disabled.
  */
-static int tick_check_new_device(struct clock_event_device *newdev)
+void tick_check_new_device(struct clock_event_device *newdev)
 {
 	struct clock_event_device *curdev;
 	struct tick_device *td;
-	int cpu, ret = NOTIFY_OK;
-	unsigned long flags;
-
-	raw_spin_lock_irqsave(&tick_device_lock, flags);
+	int cpu;
 
 	cpu = smp_processor_id();
 	if (!cpumask_test_cpu(cpu, newdev->cpumask))
@@ -225,40 +283,15 @@ static int tick_check_new_device(struct clock_event_device *newdev)
 	curdev = td->evtdev;
 
 	/* cpu local device ? */
-	if (!cpumask_equal(newdev->cpumask, cpumask_of(cpu))) {
-
-		/*
-		 * If the cpu affinity of the device interrupt can not
-		 * be set, ignore it.
-		 */
-		if (!irq_can_set_affinity(newdev->irq))
-			goto out_bc;
+	if (!tick_check_percpu(curdev, newdev, cpu))
+		goto out_bc;
 
-		/*
-		 * If we have a cpu local device already, do not replace it
-		 * by a non cpu local device
-		 */
-		if (curdev && cpumask_equal(curdev->cpumask, cpumask_of(cpu)))
-			goto out_bc;
-	}
+	/* Preference decision */
+	if (!tick_check_preferred(curdev, newdev))
+		goto out_bc;
 
-	/*
-	 * If we have an active device, then check the rating and the oneshot
-	 * feature.
-	 */
-	if (curdev) {
-		/*
-		 * Prefer one shot capable devices !
-		 */
-		if ((curdev->features & CLOCK_EVT_FEAT_ONESHOT) &&
-		    !(newdev->features & CLOCK_EVT_FEAT_ONESHOT))
-			goto out_bc;
-		/*
-		 * Check the rating
-		 */
-		if (curdev->rating >= newdev->rating)
-			goto out_bc;
-	}
+	if (!try_module_get(newdev->owner))
+		return;
 
 	/*
 	 * Replace the eventually existing device by the new
@@ -273,20 +306,13 @@ static int tick_check_new_device(struct clock_event_device *newdev)
 	tick_setup_device(td, newdev, cpu, cpumask_of(cpu));
 	if (newdev->features & CLOCK_EVT_FEAT_ONESHOT)
 		tick_oneshot_notify();
-
-	raw_spin_unlock_irqrestore(&tick_device_lock, flags);
-	return NOTIFY_STOP;
+	return;
 
 out_bc:
 	/*
 	 * Can the new device be used as a broadcast device ?
 	 */
-	if (tick_check_broadcast_device(newdev))
-		ret = NOTIFY_STOP;
-
-	raw_spin_unlock_irqrestore(&tick_device_lock, flags);
-
-	return ret;
+	tick_install_broadcast_device(newdev);
 }
 
 /*
@@ -294,7 +320,7 @@ out_bc:
  *
  * Called with interrupts disabled.
  */
-static void tick_handover_do_timer(int *cpup)
+void tick_handover_do_timer(int *cpup)
 {
 	if (*cpup == tick_do_timer_cpu) {
 		int cpu = cpumask_first(cpu_online_mask);
@@ -311,13 +337,11 @@ static void tick_handover_do_timer(int *cpup)
  * access the hardware device itself.
  * We just set the mode and remove it from the lists.
  */
-static void tick_shutdown(unsigned int *cpup)
+void tick_shutdown(unsigned int *cpup)
 {
 	struct tick_device *td = &per_cpu(tick_cpu_device, *cpup);
 	struct clock_event_device *dev = td->evtdev;
-	unsigned long flags;
 
-	raw_spin_lock_irqsave(&tick_device_lock, flags);
 	td->mode = TICKDEV_MODE_PERIODIC;
 	if (dev) {
 		/*
@@ -329,26 +353,20 @@ static void tick_shutdown(unsigned int *cpup)
 		dev->event_handler = clockevents_handle_noop;
 		td->evtdev = NULL;
 	}
-	raw_spin_unlock_irqrestore(&tick_device_lock, flags);
 }
 
-static void tick_suspend(void)
+void tick_suspend(void)
 {
 	struct tick_device *td = &__get_cpu_var(tick_cpu_device);
-	unsigned long flags;
 
-	raw_spin_lock_irqsave(&tick_device_lock, flags);
 	clockevents_shutdown(td->evtdev);
-	raw_spin_unlock_irqrestore(&tick_device_lock, flags);
 }
 
-static void tick_resume(void)
+void tick_resume(void)
 {
 	struct tick_device *td = &__get_cpu_var(tick_cpu_device);
-	unsigned long flags;
 	int broadcast = tick_resume_broadcast();
 
-	raw_spin_lock_irqsave(&tick_device_lock, flags);
 	clockevents_set_mode(td->evtdev, CLOCK_EVT_MODE_RESUME);
 
 	if (!broadcast) {
@@ -357,68 +375,12 @@ static void tick_resume(void)
 		else
 			tick_resume_oneshot();
 	}
-	raw_spin_unlock_irqrestore(&tick_device_lock, flags);
 }
 
-/*
- * Notification about clock event devices
- */
-static int tick_notify(struct notifier_block *nb, unsigned long reason,
-			       void *dev)
-{
-	switch (reason) {
-
-	case CLOCK_EVT_NOTIFY_ADD:
-		return tick_check_new_device(dev);
-
-	case CLOCK_EVT_NOTIFY_BROADCAST_ON:
-	case CLOCK_EVT_NOTIFY_BROADCAST_OFF:
-	case CLOCK_EVT_NOTIFY_BROADCAST_FORCE:
-		tick_broadcast_on_off(reason, dev);
-		break;
-
-	case CLOCK_EVT_NOTIFY_BROADCAST_ENTER:
-	case CLOCK_EVT_NOTIFY_BROADCAST_EXIT:
-		tick_broadcast_oneshot_control(reason);
-		break;
-
-	case CLOCK_EVT_NOTIFY_CPU_DYING:
-		tick_handover_do_timer(dev);
-		break;
-
-	case CLOCK_EVT_NOTIFY_CPU_DEAD:
-		tick_shutdown_broadcast_oneshot(dev);
-		tick_shutdown_broadcast(dev);
-		tick_shutdown(dev);
-		break;
-
-	case CLOCK_EVT_NOTIFY_SUSPEND:
-		tick_suspend();
-		tick_suspend_broadcast();
-		break;
-
-	case CLOCK_EVT_NOTIFY_RESUME:
-		tick_resume();
-		break;
-
-	default:
-		break;
-	}
-
-	return NOTIFY_OK;
-}
-
-static struct notifier_block tick_notifier = {
-	.notifier_call = tick_notify,
-};
-
 /**
  * tick_init - initialize the tick control
- *
- * Register the notifier with the clockevents framework
  */
 void __init tick_init(void)
 {
-	clockevents_register_notifier(&tick_notifier);
 	tick_broadcast_init();
 }
diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h
index f0299eae4602..bc906cad709b 100644
--- a/kernel/time/tick-internal.h
+++ b/kernel/time/tick-internal.h
@@ -6,6 +6,8 @@
 
 extern seqlock_t jiffies_lock;
 
+#define CS_NAME_LEN	32
+
 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BUILD
 
 #define TICK_DO_TIMER_NONE	-1
@@ -18,9 +20,19 @@ extern int tick_do_timer_cpu __read_mostly;
 
 extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
 extern void tick_handle_periodic(struct clock_event_device *dev);
+extern void tick_check_new_device(struct clock_event_device *dev);
+extern void tick_handover_do_timer(int *cpup);
+extern void tick_shutdown(unsigned int *cpup);
+extern void tick_suspend(void);
+extern void tick_resume(void);
+extern bool tick_check_replacement(struct clock_event_device *curdev,
+				   struct clock_event_device *newdev);
+extern void tick_install_replacement(struct clock_event_device *dev);
 
 extern void clockevents_shutdown(struct clock_event_device *dev);
 
+extern size_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);
+
 /*
  * NO_HZ / high resolution timer shared code
  */
@@ -90,7 +102,7 @@ static inline bool tick_broadcast_oneshot_available(void) { return false; }
  */
 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
 extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
-extern int tick_check_broadcast_device(struct clock_event_device *dev);
+extern void tick_install_broadcast_device(struct clock_event_device *dev);
 extern int tick_is_broadcast_device(struct clock_event_device *dev);
 extern void tick_broadcast_on_off(unsigned long reason, int *oncpu);
 extern void tick_shutdown_broadcast(unsigned int *cpup);
@@ -102,9 +114,8 @@ tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
 
 #else /* !BROADCAST */
 
-static inline int tick_check_broadcast_device(struct clock_event_device *dev)
+static inline void tick_install_broadcast_device(struct clock_event_device *dev)
 {
-	return 0;
 }
 
 static inline int tick_is_broadcast_device(struct clock_event_device *dev)
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index bc67d4245e1d..f4208138fbf4 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -717,6 +717,7 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts)
 	if (unlikely(!cpu_online(cpu))) {
 		if (cpu == tick_do_timer_cpu)
 			tick_do_timer_cpu = TICK_DO_TIMER_NONE;
+		return false;
 	}
 
 	if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
@@ -1168,7 +1169,7 @@ void tick_cancel_sched_timer(int cpu)
 		hrtimer_cancel(&ts->sched_timer);
 # endif
 
-	ts->nohz_mode = NOHZ_MODE_INACTIVE;
+	memset(ts, 0, sizeof(*ts));
 }
 #endif
 
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 98cd470bbe49..838fc0777b68 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -25,6 +25,7 @@
 
 #include "tick-internal.h"
 #include "ntp_internal.h"
+#include "timekeeping_internal.h"
 
 static struct timekeeper timekeeper;
 static DEFINE_RAW_SPINLOCK(timekeeper_lock);
@@ -627,11 +628,20 @@ static int change_clocksource(void *data)
 	write_seqcount_begin(&timekeeper_seq);
 
 	timekeeping_forward_now(tk);
-	if (!new->enable || new->enable(new) == 0) {
-		old = tk->clock;
-		tk_setup_internals(tk, new);
-		if (old->disable)
-			old->disable(old);
+	/*
+	 * If the cs is in module, get a module reference. Succeeds
+	 * for built-in code (owner == NULL) as well.
+	 */
+	if (try_module_get(new->owner)) {
+		if (!new->enable || new->enable(new) == 0) {
+			old = tk->clock;
+			tk_setup_internals(tk, new);
+			if (old->disable)
+				old->disable(old);
+			module_put(old->owner);
+		} else {
+			module_put(new->owner);
+		}
 	}
 	timekeeping_update(tk, true, true);
 
@@ -648,14 +658,15 @@ static int change_clocksource(void *data)
  * This function is called from clocksource.c after a new, better clock
  * source has been registered. The caller holds the clocksource_mutex.
  */
-void timekeeping_notify(struct clocksource *clock)
+int timekeeping_notify(struct clocksource *clock)
 {
 	struct timekeeper *tk = &timekeeper;
 
 	if (tk->clock == clock)
-		return;
+		return 0;
 	stop_machine(change_clocksource, clock, NULL);
 	tick_clock_notify();
+	return tk->clock == clock ? 0 : -1;
 }
 
 /**
@@ -841,6 +852,7 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk,
 	tk_xtime_add(tk, delta);
 	tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, *delta));
 	tk_set_sleep_time(tk, timespec_add(tk->total_sleep_time, *delta));
+	tk_debug_account_sleep_time(delta);
 }
 
 /**
diff --git a/kernel/time/timekeeping_debug.c b/kernel/time/timekeeping_debug.c
new file mode 100644
index 000000000000..802433a4f5eb
--- /dev/null
+++ b/kernel/time/timekeeping_debug.c
@@ -0,0 +1,72 @@
+/*
+ * debugfs file to track time spent in suspend
+ *
+ * Copyright (c) 2011, Google, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/debugfs.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/seq_file.h>
+#include <linux/time.h>
+
+static unsigned int sleep_time_bin[32] = {0};
+
+static int tk_debug_show_sleep_time(struct seq_file *s, void *data)
+{
+	unsigned int bin;
+	seq_puts(s, "      time (secs)        count\n");
+	seq_puts(s, "------------------------------\n");
+	for (bin = 0; bin < 32; bin++) {
+		if (sleep_time_bin[bin] == 0)
+			continue;
+		seq_printf(s, "%10u - %-10u %4u\n",
+			bin ? 1 << (bin - 1) : 0, 1 << bin,
+				sleep_time_bin[bin]);
+	}
+	return 0;
+}
+
+static int tk_debug_sleep_time_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, tk_debug_show_sleep_time, NULL);
+}
+
+static const struct file_operations tk_debug_sleep_time_fops = {
+	.open		= tk_debug_sleep_time_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static int __init tk_debug_sleep_time_init(void)
+{
+	struct dentry *d;
+
+	d = debugfs_create_file("sleep_time", 0444, NULL, NULL,
+		&tk_debug_sleep_time_fops);
+	if (!d) {
+		pr_err("Failed to create sleep_time debug file\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+late_initcall(tk_debug_sleep_time_init);
+
+void tk_debug_account_sleep_time(struct timespec *t)
+{
+	sleep_time_bin[fls(t->tv_sec)]++;
+}
+
diff --git a/kernel/time/timekeeping_internal.h b/kernel/time/timekeeping_internal.h
new file mode 100644
index 000000000000..13323ea08ffa
--- /dev/null
+++ b/kernel/time/timekeeping_internal.h
@@ -0,0 +1,14 @@
+#ifndef _TIMEKEEPING_INTERNAL_H
+#define _TIMEKEEPING_INTERNAL_H
+/*
+ * timekeeping debug functions
+ */
+#include <linux/time.h>
+
+#ifdef CONFIG_DEBUG_FS
+extern void tk_debug_account_sleep_time(struct timespec *t);
+#else
+#define tk_debug_account_sleep_time(x)
+#endif
+
+#endif /* _TIMEKEEPING_INTERNAL_H */
diff --git a/kernel/timer.c b/kernel/timer.c
index a860bba34412..15ffdb3f1948 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -1539,12 +1539,12 @@ static int __cpuinit init_timers_cpu(int cpu)
 			boot_done = 1;
 			base = &boot_tvec_bases;
 		}
+		spin_lock_init(&base->lock);
 		tvec_base_done[cpu] = 1;
 	} else {
 		base = per_cpu(tvec_bases, cpu);
 	}
 
-	spin_lock_init(&base->lock);
 
 	for (j = 0; j < TVN_SIZE; j++) {
 		INIT_LIST_HEAD(base->tv5.vec + j);
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index a6361178de5a..e1b653f7e1ca 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -750,7 +750,11 @@ static int filter_set_pred(struct event_filter *filter,
 
 static void __free_preds(struct event_filter *filter)
 {
+	int i;
+
 	if (filter->preds) {
+		for (i = 0; i < filter->n_preds; i++)
+			kfree(filter->preds[i].ops);
 		kfree(filter->preds);
 		filter->preds = NULL;
 	}
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 636d45fe69b3..9f46e98ba8f2 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -35,7 +35,7 @@ struct trace_probe {
 	const char		*symbol;	/* symbol name */
 	struct ftrace_event_class	class;
 	struct ftrace_event_call	call;
-	struct ftrace_event_file	**files;
+	struct ftrace_event_file * __rcu *files;
 	ssize_t			size;		/* trace entry size */
 	unsigned int		nr_args;
 	struct probe_arg	args[];
@@ -185,9 +185,14 @@ static struct trace_probe *find_trace_probe(const char *event,
 
 static int trace_probe_nr_files(struct trace_probe *tp)
 {
-	struct ftrace_event_file **file = tp->files;
+	struct ftrace_event_file **file;
 	int ret = 0;
 
+	/*
+	 * Since all tp->files updater is protected by probe_enable_lock,
+	 * we don't need to lock an rcu_read_lock.
+	 */
+	file = rcu_dereference_raw(tp->files);
 	if (file)
 		while (*(file++))
 			ret++;
@@ -209,9 +214,10 @@ enable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file)
 	mutex_lock(&probe_enable_lock);
 
 	if (file) {
-		struct ftrace_event_file **new, **old = tp->files;
+		struct ftrace_event_file **new, **old;
 		int n = trace_probe_nr_files(tp);
 
+		old = rcu_dereference_raw(tp->files);
 		/* 1 is for new one and 1 is for stopper */
 		new = kzalloc((n + 2) * sizeof(struct ftrace_event_file *),
 			      GFP_KERNEL);
@@ -251,11 +257,17 @@ enable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file)
 static int
 trace_probe_file_index(struct trace_probe *tp, struct ftrace_event_file *file)
 {
+	struct ftrace_event_file **files;
 	int i;
 
-	if (tp->files) {
-		for (i = 0; tp->files[i]; i++)
-			if (tp->files[i] == file)
+	/*
+	 * Since all tp->files updater is protected by probe_enable_lock,
+	 * we don't need to lock an rcu_read_lock.
+	 */
+	files = rcu_dereference_raw(tp->files);
+	if (files) {
+		for (i = 0; files[i]; i++)
+			if (files[i] == file)
 				return i;
 	}
 
@@ -274,10 +286,11 @@ disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file)
 	mutex_lock(&probe_enable_lock);
 
 	if (file) {
-		struct ftrace_event_file **new, **old = tp->files;
+		struct ftrace_event_file **new, **old;
 		int n = trace_probe_nr_files(tp);
 		int i, j;
 
+		old = rcu_dereference_raw(tp->files);
 		if (n == 0 || trace_probe_file_index(tp, file) < 0) {
 			ret = -EINVAL;
 			goto out_unlock;
@@ -872,9 +885,16 @@ __kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs,
 static __kprobes void
 kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs)
 {
-	struct ftrace_event_file **file = tp->files;
+	/*
+	 * Note: preempt is already disabled around the kprobe handler.
+	 * However, we still need an smp_read_barrier_depends() corresponding
+	 * to smp_wmb() in rcu_assign_pointer() to access the pointer.
+	 */
+	struct ftrace_event_file **file = rcu_dereference_raw(tp->files);
+
+	if (unlikely(!file))
+		return;
 
-	/* Note: preempt is already disabled around the kprobe handler */
 	while (*file) {
 		__kprobe_trace_func(tp, regs, *file);
 		file++;
@@ -925,9 +945,16 @@ static __kprobes void
 kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri,
 		     struct pt_regs *regs)
 {
-	struct ftrace_event_file **file = tp->files;
+	/*
+	 * Note: preempt is already disabled around the kprobe handler.
+	 * However, we still need an smp_read_barrier_depends() corresponding
+	 * to smp_wmb() in rcu_assign_pointer() to access the pointer.
+	 */
+	struct ftrace_event_file **file = rcu_dereference_raw(tp->files);
+
+	if (unlikely(!file))
+		return;
 
-	/* Note: preempt is already disabled around the kprobe handler */
 	while (*file) {
 		__kretprobe_trace_func(tp, ri, regs, *file);
 		file++;
@@ -935,7 +962,7 @@ kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri,
 }
 
 /* Event entry printers */
-enum print_line_t
+static enum print_line_t
 print_kprobe_event(struct trace_iterator *iter, int flags,
 		   struct trace_event *event)
 {
@@ -971,7 +998,7 @@ partial:
 	return TRACE_TYPE_PARTIAL_LINE;
 }
 
-enum print_line_t
+static enum print_line_t
 print_kretprobe_event(struct trace_iterator *iter, int flags,
 		      struct trace_event *event)
 {
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 4aa9f5bc6b2d..1ae602809efb 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4311,6 +4311,12 @@ bool current_is_workqueue_rescuer(void)
  * no synchronization around this function and the test result is
  * unreliable and only useful as advisory hints or for debugging.
  *
+ * If @cpu is WORK_CPU_UNBOUND, the test is performed on the local CPU.
+ * Note that both per-cpu and unbound workqueues may be associated with
+ * multiple pool_workqueues which have separate congested states.  A
+ * workqueue being congested on one CPU doesn't mean the workqueue is also
+ * contested on other CPUs / NUMA nodes.
+ *
  * RETURNS:
  * %true if congested, %false otherwise.
  */
@@ -4321,6 +4327,9 @@ bool workqueue_congested(int cpu, struct workqueue_struct *wq)
 
 	rcu_read_lock_sched();
 
+	if (cpu == WORK_CPU_UNBOUND)
+		cpu = smp_processor_id();
+
 	if (!(wq->flags & WQ_UNBOUND))
 		pwq = per_cpu_ptr(wq->cpu_pwqs, cpu);
 	else